os/kernelhwsrv/kernel/eka/memmodel/epoc/mmubase/kblockmap.cpp
changeset 0 bde4ae8d615e
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/os/kernelhwsrv/kernel/eka/memmodel/epoc/mmubase/kblockmap.cpp	Fri Jun 15 03:10:57 2012 +0200
     1.3 @@ -0,0 +1,193 @@
     1.4 +// Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
     1.5 +// All rights reserved.
     1.6 +// This component and the accompanying materials are made available
     1.7 +// under the terms of the License "Eclipse Public License v1.0"
     1.8 +// which accompanies this distribution, and is available
     1.9 +// at the URL "http://www.eclipse.org/legal/epl-v10.html".
    1.10 +//
    1.11 +// Initial Contributors:
    1.12 +// Nokia Corporation - initial contribution.
    1.13 +//
    1.14 +// Contributors:
    1.15 +//
    1.16 +// Description:
    1.17 +// e32\memmodel\epoc\mmubase\kblockmap.cpp
    1.18 +// 
    1.19 +//
    1.20 +
    1.21 +#include <memmodel/epoc/mmubase/kblockmap.h>
    1.22 +#include <e32cmn.h>
    1.23 +#include <e32cmn_private.h>
    1.24 +#include <e32atomics.h>
    1.25 +
    1.26 +#undef ASSERT
    1.27 +
    1.28 +#ifdef __KERNEL_MODE__
    1.29 +
    1.30 +#include <kernel/kernel.h>
    1.31 +#define TRACECLASS Kern
    1.32 +#undef TRACE
    1.33 +#define ASSERT(x) __NK_ASSERT_DEBUG(x)
    1.34 +#define FREE(x) Kern::Free(x)
    1.35 +
    1.36 +#define RETURN_ERROR(err, traceMsg)													 \
    1.37 +	{																				 \
    1.38 +	__KTRACE_OPT(KPAGING,Kern::Printf("DP: %s, returning error %d", traceMsg, err)); \
    1.39 +	return err;																		 \
    1.40 +	}
    1.41 +
    1.42 +#define TRACE_FATAL(x) __KTRACE_OPT(KPANIC, Kern::x)
    1.43 +
    1.44 +#else
    1.45 +
    1.46 +#include <e32debug.h>
    1.47 +#include <e32test.h>
    1.48 +#define TRACECLASS RDebug
    1.49 +extern RTest test;
    1.50 +#define ASSERT(x) test(x);
    1.51 +#define FREE(x) User::Free(x)
    1.52 +
    1.53 +#define RETURN_ERROR(err, traceMsg)								  \
    1.54 +	{															  \
    1.55 +	RDebug::Printf("DP: %s, returning error %d", traceMsg, err); \
    1.56 +	return err;													  \
    1.57 +	}
    1.58 +
    1.59 +#define TRACE_FATAL(x) RDebug::x
    1.60 +
    1.61 +#endif
    1.62 +
    1.63 +TInt TBlockMap::Initialise(const SBlockMapInfoBase& aBlockMapInfo,
    1.64 +						   TBlockMapEntryBase* aBlockMapEntries,
    1.65 +						   TInt aBlockMapEntriesSize,
    1.66 +						   TInt aReadUnitShift,
    1.67 +						   TInt aDataLengthInFile)
    1.68 +	{
    1.69 +	ASSERT(iExtents == NULL);
    1.70 +
    1.71 +	if (aBlockMapEntriesSize % sizeof(TBlockMapEntryBase) != 0)
    1.72 +		RETURN_ERROR(KErrArgument, "Size of block map is not multiple of entry size");
    1.73 +	iExtentCount = aBlockMapEntriesSize / sizeof(TBlockMapEntryBase);
    1.74 +
    1.75 +	TInt blockShift = __e32_find_ms1_32(aBlockMapInfo.iBlockGranularity);
    1.76 +	if ((1u << blockShift) != aBlockMapInfo.iBlockGranularity)
    1.77 +		RETURN_ERROR(KErrArgument, "Block granularity not a power of two");
    1.78 +	if (blockShift < aReadUnitShift)
    1.79 +		RETURN_ERROR(KErrArgument, "Block size must be greater than or equal to read unit size");
    1.80 +	TInt blockScaling = blockShift - aReadUnitShift;
    1.81 +	TInt readUnitMask = (1 << aReadUnitShift) - 1;
    1.82 +
    1.83 +	if ((aBlockMapInfo.iStartBlockAddress & ((1 << aReadUnitShift) - 1)) != 0)
    1.84 +		RETURN_ERROR(KErrArgument, "Block zero address not a multiple of read unit size");
    1.85 +	TUint blockZeroNumber = (TUint)(aBlockMapInfo.iStartBlockAddress >> aReadUnitShift);  // offset of block zero from start of partition
    1.86 +
    1.87 +	if (aBlockMapInfo.iBlockStartOffset >= aBlockMapInfo.iBlockGranularity)
    1.88 +		RETURN_ERROR(KErrArgument, "Block start offset must be less than block size");
    1.89 +
    1.90 +	if (aDataLengthInFile <= 0)
    1.91 +		RETURN_ERROR(KErrArgument, "Length of code data in file must be greater than zero"); 
    1.92 +	iDataLength = aDataLengthInFile;
    1.93 +	
    1.94 +	// Process block map data into kernel-side reprsentation
    1.95 +	TInt dataOffset = -(TInt)(aBlockMapInfo.iBlockStartOffset & readUnitMask);
    1.96 +	SExtent entry;
    1.97 +	for (TInt i = 0 ; i < iExtentCount ; ++i)
    1.98 +		{
    1.99 +		const TBlockMapEntryBase& data = aBlockMapEntries[i];
   1.100 +		entry.iDataOffset = dataOffset;
   1.101 +		entry.iBlockNumber = (data.iStartBlock << blockScaling) + blockZeroNumber;
   1.102 +		dataOffset += data.iNumberOfBlocks << blockShift;
   1.103 +		if (i == 0)
   1.104 +			{
   1.105 +			TInt adjustStartBlock = aBlockMapInfo.iBlockStartOffset >> aReadUnitShift;
   1.106 +			entry.iBlockNumber += adjustStartBlock;
   1.107 +			dataOffset -= adjustStartBlock << aReadUnitShift;
   1.108 +			}
   1.109 +		(SExtent&)data = entry;
   1.110 +		}
   1.111 +	
   1.112 +	if (dataOffset < iDataLength)
   1.113 +		RETURN_ERROR(KErrArgument, "Block map too short");
   1.114 +
   1.115 +	// Take ownership of buffer
   1.116 +	iExtents = (SExtent*) aBlockMapEntries;
   1.117 +
   1.118 +	return KErrNone;
   1.119 +	}
   1.120 +
   1.121 +TBlockMap::TBlockMap()
   1.122 +	: iExtents(NULL)
   1.123 +	{
   1.124 +	}
   1.125 +
   1.126 +TBlockMap::~TBlockMap()
   1.127 +	{
   1.128 +	FREE(iExtents);
   1.129 +	}
   1.130 +
   1.131 +TInt TBlockMap::FindFirstExtent(TInt aPos) const
   1.132 +	{
   1.133 +	if (aPos < 0 || aPos >= iDataLength)
   1.134 +		return KErrArgument;
   1.135 +	RArray<SExtent> extents(sizeof(SExtent), iExtents, iExtentCount);
   1.136 +	SExtent findEntry = { aPos, 0 };
   1.137 +	TInt i = -1;
   1.138 +	extents.SpecificFindInSignedKeyOrder(findEntry, i, EArrayFindMode_Last);
   1.139 +	--i;
   1.140 +	if (i < 0 || i >= iExtentCount)
   1.141 +		return KErrArgument;
   1.142 +	return i;
   1.143 +	}
   1.144 +
   1.145 +TInt TBlockMap::Read(TLinAddr aBuffer, TInt aPos, TInt aLength, TInt aReadUnitShift, TReadFunc aReadFunc, TAny* aArg1, TAny* aArg2) const
   1.146 +	{
   1.147 +	TInt dataOffset = aPos;
   1.148 +	TInt remain = aLength;
   1.149 +	TInt readUnitMask = (1 << aReadUnitShift) - 1;
   1.150 +	
   1.151 +	TInt i = FindFirstExtent(dataOffset);
   1.152 +	if (i < 0)
   1.153 +		return i;
   1.154 +	TInt bufferStart = (dataOffset - Extent(i).iDataOffset) & readUnitMask;  // start of page in buffer
   1.155 +	TInt bufferOffset = 0;
   1.156 +	while (remain > 0)
   1.157 +		{
   1.158 + 		if (i >= Count())
   1.159 +			return KErrArgument;
   1.160 +		
   1.161 +		const SExtent& extent = Extent(i);
   1.162 +		TInt blockStartOffset = dataOffset - extent.iDataOffset;
   1.163 +		TInt blockNumber = extent.iBlockNumber + (blockStartOffset >> aReadUnitShift);
   1.164 +		TInt nextExtentStart = i == Count() - 1 ? iDataLength : Extent(i + 1).iDataOffset;
   1.165 +		TInt dataSize = Min(remain, nextExtentStart - dataOffset);
   1.166 +		TInt blockCount = (dataSize + (blockStartOffset & readUnitMask) + readUnitMask) >> aReadUnitShift;
   1.167 +		
   1.168 +		TInt r = aReadFunc(aArg1, aArg2, aBuffer + bufferOffset, blockNumber, blockCount);
   1.169 +		if (r != KErrNone)
   1.170 +			{
   1.171 +			TRACE_FATAL(Printf("TBlockMap::Read: error reading media at %08x + %x: %d", blockNumber << aReadUnitShift, blockCount << aReadUnitShift, r));
   1.172 +			return r;
   1.173 +			}
   1.174 +
   1.175 +		bufferOffset += blockCount << aReadUnitShift;
   1.176 +		dataOffset += dataSize;
   1.177 +		remain -= dataSize;
   1.178 +		++i;
   1.179 +		}
   1.180 +	
   1.181 +	return bufferStart;
   1.182 +	}
   1.183 +
   1.184 +#ifdef _DEBUG
   1.185 +
   1.186 +void TBlockMap::Dump() const
   1.187 +	{
   1.188 +	TRACECLASS::Printf("TBlockMap:");
   1.189 +	for (TInt i = 0 ; i < Count() ; ++i)
   1.190 +		{
   1.191 +		TInt nextExtentStart = i == Count() - 1 ? iDataLength : Extent(i + 1).iDataOffset;
   1.192 +		TRACECLASS::Printf("  %d: %08x -> %08x: %08x", i, Extent(i).iDataOffset, nextExtentStart, Extent(i).iBlockNumber);
   1.193 +		}
   1.194 +	}
   1.195 +
   1.196 +#endif